Data centers may host applications and store large amounts of data for an organization or multiple organizations. An enterprise data center may be privately owned and discretely provide services for a number of customers, with each customer using data center resources by way of private networks. In addition, these data centers provide server and desktop virtualization that is dramatically changing the enterprise network by creating many virtual “networks” which connect virtual machines and the physical networks through virtual switches. In this new network paradigm, many new network service requirements are imposed on modern Information Technology (IT) network infrastructure.
The service requirements (e.g., load balancing, wide area network (WAN) acceleration, network security, etc.) have traditionally been provided by inline network appliances, referred to as service nodes. These inline network appliances do not scale well in a virtualized network environment in which end point applications are provided by virtual machines. At any given point in time, virtual machines are being instantiated, stopped, and dynamically migrated to another physical host. In a virtual network, the network services should support this dynamic provisioning scalability, and virtual machine mobility.